Sonographic features of axillary lymphadenopathy caused by Kikuchi disease

Kikuchi-Fujimoto disease: A comprehensive review

Kikuchi-Fujimoto disease, a rare form of necrotizing lymphadenitis, is an uncommon, benign, self-limiting disorder of obscure etiology. It affects mostly young adults of both genders. Clinically, it presents with fever and lymphadenopathy of a firm to rubbery consistency frequently involving cervical lymph nodes while weight loss, splenomegaly, leucopenia, and elevated erythrocyte sedimentation rate feature in severely affected patients. Cutaneous involvement occurs in about 30%-40% of cases as facial erythema and nonspecific erythematous papules, plaques, acneiform or morbilliform lesions of great histologic heterogeneity. Both Kikuchi-Fujimoto disease and systemic lupus erythematosus share an obscure and complex relationship as systemic lupus erythematosus may occasionally precede, develop subsequently, or sometimes be associated concurrently with Kikuchi-Fujimoto disease. It is often mistaken for non-Hodgkin lymphoma while lupus lymphadenitis, cat-scratch disease, Sweet's syndrome, Still's disease, drug eruptions, infectious mononucleosis, and viral or tubercular lymphadenitis are other common differentials. Fine needle aspiration cytology mostly has features of nonspecific reactive lymphadenitis and immunohistochemistry studies usually show variable features of uncertain diagnostic value. Since its diagnosis is exclusively from histopathology, it needs to be evaluated more carefully; an early lymph node biopsy will obviate the need for unnecessary investigations and therapeutic trials. Its treatment with systemic corticosteroids, hydroxychloroquine, or antimicrobial agents mostly remains empirical. The article reviews clinicoepidemiological, diagnostic, and management aspects of KFD from the perspective of practicing clinicians.

Kikuchi-Fujimoto-like lymphadenopathy following COVID-19 vaccine: diagnosis and management

A woman in her mid 40s presented for breast imaging after 1 week of painful and enlarged right axillary lymphadenopathy. She denied history of fever, weight loss, night sweats fatigue, cat scratch or other trauma. She received the second dose of Pfizer COVID-19 vaccine 3 months previously on the contralateral arm. A mammogram demonstrated a single, asymmetric, large and dense right axillary lymph node. Ultrasound confirmed a 2.5 cm lymph node with cortical thickening of 0.6 cm. Ultrasound-guided core biopsy showed necrotising lymphadenitis with associated aggregates of histiocytes and plasmacytoid dendritic cells. Potential causes of necrotising adenitis including Bartonella, tuberculosis, Epstein-Barr Virus, herpes simplex virus, systemic lupus erythematosus and lymphoma were excluded. In the absence of any identifiable infectious or autoimmune causes, and given the temporal relatedness with vaccine administration, it was determined that the Kikuchi-Fujimoto-like necrotising lymphadenitis was likely secondary to the COVID-19 vaccine. To date, there has been no casual association made between the COVID-19 vaccine and KFD necrotising lymphadenitis.

Kikuchi Disease with enlargement of intramammary lymph node

We describe a rare case of intramammary lymphadenopathy due to Kikuchi-Fujimoto disease. A 15-year old female presented to the Breast Clinic with complaints of a tender, palpable right breast lump. An ultrasound of the area of concern demonstrated an enlarged 2.9 cm intramammary lymph node with preservation of the fatty hilum. An ultrasound guided core biopsy of the lymph node confirmed the diagnosis of Kikuchi-Fujimoto disease.

Development of Kikuchi-Fujimoto disease after a cervical lymph node metastasis of mucoepidermoid carcinoma: a case report

Kikuchi-Fujimoto disease (KFD) was first reported by Kikuchi and Fujimoto in 1972 as a rare disease with lymphadenitis of unknown etiology. KFD is characterized by the main symptoms of fever and enlarged cervical lymph nodes (LNs), which are similar to the features of other LN-associated diseases. Therefore, it is difficult to diagnose this condition. We report the case of a 24-year-old woman who presented with KFD after surgery to treat a mucoepidermoid carcinoma of the palate and dissection of the left neck. The patient presented with a fever and right cervical lymphadenopathy when she visited our department for a regular follow-up related to the mucoepidermoid carcinoma. The results of computed tomography and ultrasonography evaluations led to a clinical diagnosis of lymph node metastasis, and a right neck dissection was performed. However, the pathological tissue analysis did not suggest malignancy but showed necrosis and various cellular infiltrates. We made a diagnosis of KFD from these clinical and pathological features. KFD may be misdiagnosed as a LN-associated disease such as metastasis. Clinically, KFD should be considered in patients with head and neck cancer who present with cervical lymphadenopathy.

Pre-Operative Evaluation of Axillary Lymph Node Status in Patients with Suspected Breast Cancer Using Shear Wave Elastography

The aim of this study was to evaluate shear wave elastography (SWE) for pre-operative evaluation of axillary lymph node (LN) status in patients with suspected breast cancer. A total of 130 axillary LNs in 130 patients who underwent SWE before fine-needle aspiration, core biopsy or surgery were analyzed. On gray-scale images, long and short axes, shape (elliptical or round), border (sharp or unsharp) and cortical thickening (concentric, eccentric or no fatty hilum) of LNs were assessed. On SWE, mean, maximum, minimum, standard deviation and the lesion-to-fat ratio (E_ratio) values of elasticity were collected. Gray-scale and SWE features were compared statistically between metastatic and benign LNs using the χ²-test and independent t-test. Diagnostic performance of each feature was evaluated using the area under the receiver operating characteristic curve (AUC). Logistic regression analysis was used to determine gray-scale or SWE features independently associated with metastatic LNs. Of the 130 LNs, 65 (50%) were metastatic and 65 (50%) were benign after surgery. Metastatic LNs were significantly larger (p = 0.018); had higher elasticity indexes at SWE (p < 0.0001); and had higher proportions of round shape (p = 0.033), unsharp border (p = 0.048) and eccentric cortical thickening or no fatty hilum (p = 0.005) compared with benign LNs. On multivariate analysis, E_ratio was independently associated with metastatic LNs (odds ratio = 3.312, p = 0.008). E_ratio had the highest AUC among gray-scale (0.582-0.719) and SWE (0.900-0.950) variables. SWE had good diagnostic performance in metastatic axillary LNs, and E_ratio was independently associated with metastatic LNs.

Kikuchi-Fujimoto disease in the regional lymph nodes with node metastasis in a patient with tongue cancer: A case report and literature review

Kikuchi-Fujimoto disease (KFD), also known as histiocytic necrotizing lymphadenitis, is a rare self-limiting disorder typically affecting the cervical lymph nodes (LNs), which is often misdiagnosed as other LN-associated diseases. KFD frequently presents with necrotic lesions and recurrences, which are also features of metastatic LNs. Clinicians may thus suspect LN metastasis when they encounter ipsilateral cervical lymphadenopathy in a patient with head and neck cancer. The present study reports the case of a 48-year-old man with tongue cancer and KFD affecting the right edge of his tongue and ipsilateral cervical LNs. LN metastasis was initially suspected, but pathological examination of the dissected LNs revealed one necrotic metastatic lesion and two necrotic KFD lesions. Ipsilateral cervical lymphadenopathy recurred 6 years after the initial surgery, and it was not possible to differentiate clinically between a second primary tumor and recurrent KFD prior to treatment. To the best of our knowledge, this is the first reported case of simultaneous tongue cancer, regional LN metastasis and KFD. This highlights the requirement to consider KFD in the event of LNs with necrotic lesions but no cancerous cells. A combination of clinical and pathological approaches may aid in the diagnosis of KFD, in addition to ruling out LN metastasis in initial and recurrent lymphadenopathies. The present study indicate that a diagnosis of KFD should be considered in patients with head and neck cancer that exhibit necrotic LNs lacking cancerous cells. This is important, as misdiagnosis of KFD as LN metastasis may lead to unnecessary adjuvant therapy.

Role of Real-Time Elastography in the Evaluation of Cervical Lymph Nodes in Patients with Kikuchi Disease

The purpose of this study was to compare the use of conventional ultrasound (US) and real-time elastography (RTE) in Kikuchi disease (KD, n = 48) and malignant cervical lymphadenopathy (n = 100) and to evaluate the role of RTE in patients suspected of having KD. In univariate analysis, conventional US revealed each benign feature more frequently in KD than in malignant lymphadenopathy (p < 0.05). However, a considerable number of cases (29, 60.4%) of KD were assessed as malignant with US. KD was assessed as benign by RTE more frequently than malignant lymphadenopathy (37 [77.1%] vs. 37 [37.0%], p < 0.001). In multivariate analysis, perinodal hyper-echogenicity was predictive of KD (odds ratio: 67.25, confidence interval: 10.95-413.04, p < 0.001). There was a tendency for KD to be assessed as malignant with conventional US, but benign with RTE. RTE can help to avoid unnecessary biopsy in patients suspected of having KD on the basis of conventional US.

Clinical Importance and Sonographic Features of Nonpalpable Axillary Lymphadenopathy Identified on Breast Sonography in Patients Without Malignancy

OBJECTIVES

The purpose of this study was to evaluate the clinical importance and sonographic features of nonpalpable axillary lymphadenopathy identified on breast sonography in patients without malignancy.

METHODS

Our study included 71 women and 2 men (mean age, 47.5 years; range, 16-69 years) with axillary lymphadenopathy identified on breast sonography. None of the 73 patients had known malignancy or presented with palpable lymph nodes or symptoms of mastitis. The lesions were pathologically diagnosed in 53 patients by surgical biopsy (n = 8), ultrasound-guided core needle biopsy (n = 17), or ultrasound -guided fine needle aspiration (n = 28). Twenty patients underwent follow-up imaging for 6 to 60 months (mean, 17 months). The sonographic features of the axillary lymph nodes were analyzed for all patients.

RESULTS

The final diagnoses included benign reactive hyperplasia (n = 45), Kikuchi disease (n = 4), tuberculosis (n = 3), and sarcoidosis (n = 1). None of the 20 patients who underwent follow-up imaging developed malignancy. Suspicious sonographic features were frequently observed (loss of the fatty hilum, round shape, abnormal cortical thickening, and marked hypoechogenicity: 79.5%, 75.3%, 82.1%, and 9.6%, respectively) and were mostly complex, with the most common combination being a round shape and loss of the fatty hilum in 61.6% patients.

CONCLUSIONS

No malignancy was detected in all 73 patients, despite frequent manifestations of complex and extremely suspicious sonographic features. Short-term follow-up imaging rather than immediate biopsy can be recommended for nonpalpable lymphadenopathy in patients without known malignancy.

Comparison of Ultrasonographic Findings of Biopsy-Proven Tuberculous Lymphadenitis and Kikuchi Disease

Objective

Although tuberculous lymphadenitis and Kikuchi disease are common causes of cervical lymphadenopathy in Asians and exhibit similar clinical manifestations, their treatment strategies are totally different. The purpose of this study was to identify ultrasonographic features that distinguish these two diseases.

Materials and Methods

This study was approved by the Institutional Review Board. The study included 77 patients with tuberculous lymphadenitis and 135 patients with Kikuchi disease. The sex and age distributions of the patients were analyzed. The size and shape of lymph nodes (LNs), presence of conglomeration, increased perinodal echogenicity, echogenic hilum, posterior neck involvement, internal calcification, patterns of internal necrosis, laterality of involved LNs, and hilar vascular patterns on ultrasonography were compared between the two groups. Multiple logistic regression analysis was conducted to identify independent findings to discriminate tuberculous lymphadenitis from Kikuchi disease. Finally, diagnostic accuracies were calculated using the independent findings.

Results

The presence of an echogenic hilum, internal calcification, patterns of internal necrosis, and LN hilar vascular structures on power Doppler ultrasonography were independent findings that discriminated tuberculous lymphadenitis from Kikuchi disease. The diagnostic accuracy of each of these four factors was 84.9% (181/212), 76.9% (163/212), 84% (178/212), and 89.2% (189/212), respectively. A combination of internal calcification and hilar vascular structures showed the best accuracy of 89.6% (190/212) (sensitivity, 86.7% [117/135]; specificity, 94.8% [73/77]) for diagnosing Kikuchi disease.

Conclusion

The presence of an echogenic hilum, internal calcification, pattern of internal necrosis, and LN hilar vascular structures are useful ultrasonographic findings to differentiate tuberculous lymphadenitis from Kikuchi disease.

Kikuchi's Disease: A Diagnostic Dilemma

Cervical lymphadenopathy is one of the common presentations in present day surgical practise. The causes may vary from gastrointestinal malignancy indicating a grave prognosis to nonspecfic lymphadenopathy secondary to infection or trauma to the extremity which is self-limiting. Diagnosis most often requires contributions from pathologist as well as radiologist in addition to a detailed clinical examination. We are presenting a case of Kikuchi's disease which mimics tuberculosis and often leads to diagnostic dilemma.

Histiocytic necrotising lymphadenitis (Kikuchi-Fujimoto disease) of axillary lymph nodes

Kikuchi-Fujimoto disease (KFD) or histiocytic necrotising lymphadenitis is a rare entity, occurring most commonly in young Asian adults. KFD is characterised by fever with tender lymph node enlargement. The cervical group of lymph nodes is most commonly involved, and the diagnosis is conclusively made by lymph node biopsy and histopathology. KFD is a self-limiting condition, which usually resolves over 1-4 months. Symptomatic treatment with antipyretics and/or non-steroidal anti-inflammatory drugs is recommended. Here we describe an uncommon presentation of KFD in a young woman in which only the axillary lymph nodes were enlarged.

Imaging findings of variable axillary mass and axillary lymphadenopathy

The axilla is a triangular space that contains mesenchymal tissues such as fat, vessels, nerves and lymph nodes, from which various diseases can develop. This article describes axillary masses and axillary lymphadenopathies using imaging findings from techniques such as ultrasonography, mammography, computed tomography and magnetic resonance imaging. Awareness of the characteristic imaging findings of disease entities that cause axillary masses and various axillary lymphadenopathies will help in the accurate diagnosis of axillary lesions.

18F-FDG PET/CT findings in patients with Kikuchi disease

PURPOSE

Kikuchi disease (KD) is a benign and self-limited syndrome characterized by cervical lymphadenopathy. This study evaluated 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) findings in patients with KD and analyzed their imaging features.

PATIENTS, MATERIAL, METHODS

We evaluated the FDG PET/CT findings of 22 patients (14 men, 8 women) with KD, ranging in age from 9 to 73 years. All patients had been diagnosed based on the pathological findings of biopsy. We examined the locations, metabolic activity and size of hypermetabolic lymph nodes (LNs) on FDG PET/CT imaging with medical history including laboratory results.

RESULTS

Among the 22 patients, we identified 619 hypermetabolic LNs which had maximum standard uptake value (SUVmax) above 3.0. The 16 patients were studied with FDG PET/CT to identify the cause of fever, another 5 patients for their neck masses, and the remaining patient for his left inguinal mass. Hypermetabolic LNs were noted in neck (18 bilaterally, 2 right, 1 left) of 21 patients, axilla of 10, mediastinum of 9, abdomen of 17, pelvis of 6, and inguinal area of 3. The SUVmax of FDG uptake in affected LNs by patient base analysis were 6.2-29.4. Of the 619 hypermetabolic LNs identified, 440 LNs (71.1%) were less than 10 mm in their short axis determined by CT, and were occasionally aggregated. No patient showed solid organ hypermetabolic lesion in FDG PET/CT.

CONCLUSION

Kikuchi disease could present multiple hypermetabolic LNs in body on FDG PET/CT. Based on the physical findings, consideration of the generalized distribution of the relatively small-sized hypermetabolic LNs, FDG PET/CT may be useful as a diagnostic tool in cases of Kikuchi disease.

Gray scale and power Doppler study of biopsy-proven Kikuchi disease

OBJECTIVES

Kikuchi disease is a benign, self-limiting cause of cervical lymphadenopathy. It can show sonographic features similar to those of other common causes of lymphadenopathy. The purpose of this study was to characterize the sonographic features of Kikuchi disease that can contribute in differentiating between Kikuchi disease and other diseases causing cervical lymphadenopathy.

METHODS

Sonographic findings of 175 patients with biopsy-proven Kikuchi disease were retrospectively reviewed. The mean age of the patients was 27.3 years, and the female to male ratio was 3.5:1. All patients had undergone sonographically guided core biopsy. Pathologic findings were classified into proliferative (n = 57), necrotizing (n = 109), and xanthomatous (n = 9) types. On gray scale sonography, lymph nodes were assessed by their size, shape (shortest/longest axis ratio), location, echogenicity, presence of conglomeration, gross necrosis, calcification, echogenic nodal hilum, and increased perinodal echogenicity. The vascular pattern was assessed on power Doppler imaging.

RESULTS

The mean maximum diameter of the lymph nodes was 1.6 cm. Forty-four percent of them (77 of 175) were oval (shortest/longest axis ratio, 0.5-0.7) and 48% (84 of 175) were elongated (shortest/longest axis ratio, <0.5). Most were located in levels II and V. Seventeen lymph nodes showed gross necrosis, and none showed calcification. One hundred fifty-two lymph nodes (86.8%) had an echogenic hilum, and 76% (133 of 175) showed increased perinodal echogenicity. Increased perinodal echogenicity was seen in 93.5% of the necrotizing type (102 of 109) and 43.8% of the proliferative type (25 of 57); the difference between the two types was statistically significant (P = .001). Normal (n = 161), displaced (n = 13), and absent (n = 1) hilar vascularity was seen on power Doppler studies.

CONCLUSIONS

Sonographic findings of Kikuchi disease can contribute to the differentiation between Kikuchi disease and other causes of cervical lymphadenopathy.

Kikuchi-Fujimoto disease with spontaneous subdural hematoma in a middle-aged Hispanic male

Kikuchi-Fujimoto disease (KFD) is an uncommon disorder that usually presents in young adults of Asian descent with fever and cervical lymphadenopathy. Clinically, this disease is often misdiagnosed as lymphoma or tuberculosis, and biopsy is needed for confirmation. The authors report an unusual case of KFD in a Hispanic male presenting with a subacute subdural hematoma, whose care was complicated by extranodal features not typically associated with KFD. The clinical, histopathologic, and radiographic manifestations of KFD are discussed.

Kikuchi's disease

Kikuchi disease is an idiopathic, generally self-limiting cause for lymphadenitis that can be clinically and histologically mistaken for lymphoma or systemic lupus erythematosus. Differentiating this disease from common lymphatic disorder is extremely important from the pathologist's point of view, which is highlighted in the article.

Axillary and intramammary lymphadenopathy caused by Kikuchi-Fujimoto disease mimicking malignant lymphoma

We describe a rare case of intramammary and axillary lymphadenopathy caused by Kikuchi-Fujimoto disease (KFD). A 30-year-old woman presented with enlarged axillary lymph nodes and a right breast mass with tenderness. Computed tomography, ultrasonography, F-2-deoxy-fluoro-D-glucose positron emission tomography and fine-needle aspiration cytology were performed, and malignant lymphoma (ML) was suspected. Histological diagnosis of a needle biopsy and surgical specimen showed histiocytic necrotizing lymphadenitis. It is important to differentiate KFD from ML because of differences in treatment choice and clinical outcome.